Removal of sulphur and sulphur compounds from hydrocarbon-oil distillates



Patented July 27, 192

UNITED STATLESV PATENT OFFICE.

GERALD L. WENDT, OF CHICAGO, ILLINOIS, ASSIGNOR TO STANDARD OILCOMPANY,- OF WHITIN G, INDIANA, AND CHICAGO; ILLINOIS, A CORPORATION OFINDIANA.

REMOVAL OF SULPHUR AND 'SULPHUR COMPOUNDS FROM HYDBOCARIBON OILDISTILLATES. i

No Drawing.

The present invention relates to the re- 'I'noval of sulphur and sulphurcompounds and certain otherstocks containing gasoline andkeroscnefractions which are, in ordinary refinery practice, treated for the re-.moval of sulphur and subsequently redistilled or rerun. It hasparticularly .to do with the treatment of such oils, which, after theredistillation just referred to, become sour or show a reaction withdoctor.

It has now been found that the formation of products on redistillationwhich cause sourness of the oiland cause it to give the doctor reactionmay be avoided in the following manner.

The oil, containing gasoline and heavier fractions, is treated in theusual manner with doctor solution; that is, with a solution of sodiumhydroxide of about 10 to 20 Baum saturated with litharge, andcontaining, if desired, a greater or less quantity of the precipitate orsettlings formed in the doctor solution by a previous treatment withoil. After this customary sweetening treatment, the treated oil issubjected to dis tillation, the temperature being carried to a maximumof 400 F., and preferably not higher than 350 F. In carrying out thedistillation, the oil may be brought under atmospheric pressureconditions to thedesired upper limit of temperature, say 350 F.

As the distillation is continued, the temperature is held constant or,at least, not per- -maximum vacuum required is Application filed July16, 1924. Serial No. 726,378.

mitted to rise above the predetermined maximum, an the pressure upon thedistilling oil is reduced to cause its distillation or va-: porizationto continue. The reduction of pressure is continued until the desiredproducts have been removed from the distilling oil without exceeding thepredetermined maximum temperature. The amount of dependent upon thecharacter of thedistillate product desired. Thus, for the removal of agasoline-like product having a maximum boiling point of 425 F, a maximumvacuum of about 20 inches may be required. The distillate and residueformed by distillation under these conditions, with a maximum.temperature not exceeding 400 F., and preferably 350 F., are found to besweet and not to give the doctor reactipn or the corrosion test forsulphur.

I claim:

The method of refining distillate oils containing products within thegasoline and kerosene boiling point range of the class hereinbeforedescribed comprising treating such oils with doctor solution, and.subsequently distilling the treated oil by bringing the oil underatmospheric pressure to a maximum temperature not exceeding 400F.,' andcontinuing the heating of said oil withreduction of pressure and withoutGERALD L. WENDT.

